Gripping device



Dec. 2, 1941. M ow -3y 2,264,480

GRIPPING pl aihcm 4 Filed Feb. 2'8, 1958 a Sheets-Sheet 1 INVENTOR ATTORNEY Dec. 2,1941. F. M. OWEN 2,264,430

' GRIPPING DEVICE Filed Feb. 28, 1938 3 Sheets-Sheet 2 F%INVENTOR Dec. 2, 1941. F. M. OWEN GRIPPING DEVICE 3 Sheets-Sheet 3 Filed Feb. 28, 1938 M WW 4 n W r v Ill-I'll lllullll- 7 f 5 7/ 7 1 /4 1 5 m/ E 8 8 INVENTOR.

BY M ATTORNEY.

Patented Dec. 2, 1941 UNITED STATES PATENT opp- E I 2,284,480 N if GRIPPINGDEVICE a Claims. (01. zap-9s) The invention relates mechanical means for positively gripping various elements.

The invention consists substantially of the provision, in various embodiments for numerous purposes, of mechanical gripping mechanism utilizing one general principal, viz: a flexible metal disc or washer slightly distortable by contact I with the element to be gripped.

In the embodiments hereinbelow described a few of the various forms of utilizing this principle are explained in construction and function, but obviously other embodiments could well be conceived and put into practical use without departing from the general principle involved.

The invention in its most general mechanical form consists of a series of spaced superposed flexible discs of some suitable material preferably spring steel, and means for retaining the discs and their spacers in their alined positions.

The prime object of the invention is to provide a simple gripping means which will be positive in action, compact and economical to manufacture.

Another object is the provision of a fishing tool adapted to pack-ofl with the "flsh whereby circulation of a fluid may be accomplished to assist in washing the fish" free from entanglements.

Other objects of the invention are the provision of such a device having universal utility; which may be designed to grip either the inside or outside of one or more elements; which may be designed to grip such element or elements having various cross-sectional configuration and bores; which will be durable; and, which will be 35 signed as an inside coupling'for two abutting 5 tubular elements; I Figure 5 is a fragmentary perspective view of the invention designed for couplingtwo abutting elements of angular cross-section;

Figure dis a typical section taken substantially along the line AA of Fig. 1;

0 upon the other.

Figure '7 is a similar view along the same line but disclosing a disc of slightly struction;

Figure 8 is a similar view disclosing a discior :zipping a hollow element having a hexagonal re; Figure 9 is a similar view disclosing a disc'i'or gripping a hollow element having a square bore:

Figure 10 is.a typical sectional view taken substantially along the line B--B of Fig. 2;

Figure 11 is a similar view disclosing a discfor gripping the exterior of an elementwhich is square in cross-section:

Figure 1-2 is a similar view showing a solid disc" for use in place of the discs of Fig. 2;

Figure 13 is a fragmentary elevational view showing the deformations carried by the discs in their preferred embodiment, and which may A be carried by either the inside or outside edge of an overshot," and including a pack-off structure; and,

Figure 16 is a similar view of a spear."

Like characters of reference designate like parts in all of theflgures.

Refer now more particularly to Fig. 1 in which the invention is embodied in the form of an oil field fishing tool commonly known as a "spear," and wherein the reference numeral indicates a well casing within which is shown the upper end portion 2 of a tubular element which, for pur-.

pose of description, may be consideredto be the upper end of a section of drill stem or tubing which has been broken OH in thewell, below the earth's surface.

As a means for engaging the element 2 or "fish" in order that it may be withdrawn from the well. the following mechanism is provided. A spear head 3, conical in form is equipped with an abrupt shoulder 4 and an axial, upstanding, reduced pro- .iection 5 thereabove which has threads 6 around its upper end portion. Fitting snugly around the projection 5 are a plurality of alternate discs I (Fig. 6) and spacers 8 which are stacked one The spacers 8 are preferably made of any suitable substance such as softsteel, and the discs I are preferably made of sheet spring steel, and are of an outside diameter slightly larger than the bore 9 .of the "fish" 2. Each of the discs I is, in its most usual form,

diil'erent conprovided with a plurality of radiating slits ll spaced radially around the periphery of the disc (Fig. 6). As may best be seen in Fig. 13 the teeth or the portions II of the disc lying between the slits III, are bent slightly at an angle with relation to each other, and similar edge faces of each are pointed at similar angles with relation to the plane of the body of the disc.

The threads 6 of the projection receive an interiorly threaded body I2 which when tightened down compresses the discs I and spacers I against the shoulder 4 and hold them rigidly in place. The upper end of the body 12 is equipped with an exteriorly threaded pin." for connecting the lower end of a string of drill pipe or other means whereby the tool may be lowered into the well for engaging the fish."

In fishing for a fish" such as the element 2 for instance. it is possible to ascertain from the recovered portion thereof, the approximate diameter of the bore 9. Consequently, the tool used for the particular job will be constructed with the outside diameter of its discs I slightly greater than the inside diameter of the fish."- When the head 3 is forced downwardly into the bore 9 by weight thereabove, the teeth II of the discs I are bent slightly in an upward direction due to their contact with the walls of the fish. Very little weight is required to accomplish the upward bending of the teeth due to the fact that the discs are held apart by the spacers and consequently only one disc is distorted at a time. The lower end HI of the body l2 acts as a stop when in contact with the upper end of the fish-H After insertion of the tool in the fish, upward movement thereof causes the toothed peripheries of the discs I to frictionally engage the walls of the fish," and, since there is insufilcient space between the walls and the projection 5 for the teeth to buckle and turn downwardly, the fish must necessarily move upwardly with the tool.

After engagement of the tool with the "fish, should it be found that the fish" is so tightly caught in the well that it is impossible to pull it loose, it would then become necessary to release the tool from the fish. This is accomplished as follows:

Since the teeth ll all have their similar edges disposed at similar angles with relation to the plane of the bodies of the discs (Fig. 13), when the tool is rotated in a direction in which the upwardly pointed edges of the teeth II are the leading edges, the teeth act against the walls of the "fish the same as if the tool had been threaded thereinto, and the tool therefore is merely unscrewed from the-fish.

As a means for insuring rotation of the discs I with the tool, thediscs may be splined to the projection 5. In Figure 1. the reference numeral I5 may represent either a longitudinally extending rib or a groove for accomplishing the desired connection. As may be seen in Fig. 6, this embodiment depicts l5 as being a groove.

in the form of a fishing tool knownin oil field parlance as an overshot." This tool consists substantially of an axially bored body 20 the lower portion 2| of the bore of which is enlarged and tapers downwardly and outwar y. an abrupt annular shoulder 22 being formed above the upper end of the enlargement 2|. A plurality of discs 23 and spacers 24 are alternately superposed upon each other and aresupported by the shoulder 22. A head 2! is threaded upon the upper end of the body 20 and when tightened down impinges the discs and spacers against the shoulder 22 holding them rigidly in place and the upper end of the head 28 carries threaded pin I3. As best seen in Fig. 10, the discs of this embodiment are provided with the slits l0 radially spaced around their inner edges whereby the teeth II thus formed may engage the exterior of the "fish 2. As previously described with reference to Fig. 1, the teeth II of the present embodiment are also bent at an angle with relation to the plane of the disc bodies in the manner illustrated in Fig. 13, and this tool is also released from the "fish by rotation as previously described. The discs 23 may also be splined to the body 20 as were the discs I of Fig. 1 (Fig. 10). It is thought operation of the present embodiment will be obvious.

In Fi 3 the invention is shown embodied in the form of an outside coupling for two alined pipes or shafts 26 and 21. In this embodiment, the discs 23 and spacers 24 are confined in a bowl formed of two hollow threadedly connectcd body sections 28 and 29. The opposite ends of these sections are open and are equipped with outwardly tapered or flared orifices 30 for expediting insertion of the elements 28 and 21. An annular dividing ring 3| is provided for receiving the adjacent ends of the elements, and this ring may be made of metal, or if desired can be formed of rubber so that a fiuid tight joint may be had when fluid carrying elements are to be coupled together.

In Fig. 4 an inside coupling is disclosed for engaging two tubular elements or pipes 22 and 33. In this embodiment the coupling consists substantially of a body 34 having an annular shoulder 35, a smaller projection 38 for receiving the discs I and spacers I, and a threaded cap 31 threaded upon the end of the projection for firmly retaining the discs and spacers. A dividing ring 3| is provided around the projection between the adjacent ends of the elements 32 and 33.

In the embodiments illustrated in Figs. 3 and 4, the elements are coupled together by merely forcing them into the bowl, or over the tool, as the case may be, and in both instances, may be uncoupled by rotation 01 the elements in opposite directions.

In Fig. 5 is illustrated a tool somewhat similar to the coupling of Fig. 3, but designed to engage the outside of two alined elements 38 and 39 which are angular in cross-section. In this embodiment deformable gripping elements 23-A and spacers 24-A are provided in lieu of the discs 23 and spacers 24 of Fig. 3. The'gripping elements and spacers are rectangular and fit snugly within a metal housing or box 40 which is open at both ends to receive the elements 30 and 39.

The box of Fig. 5 is shown with a solid body, and when so formed, no means is provided for releasing the elements 38 and 39. However, it is contemplated to form the box in two halves longitudinally hinged together so that the elements may be released at will. In this case suitable latching means would be furnished, and the gripping elements 23-A and the spacers IL-A would also be made in section. A divider 3l-A is located between the adjacent ends of the elements. This tool can readily be designed with only one end open to receive,. for instance .the element 39, and when rigidly attached to a work bench or similar s'upport,- may be used for a quick acting vise or chuck for retaining a piece upon which work is to be done.

It may be found for some purposes that there is no occasion for releasing the various tools from the element or elements with which they have been previously engaged. In this event, the "spear" type tools, or those operating inside of the fish," may be equipped with solid discs l-A of the type shown in Fig. 7 in which the slits l have been eliminated, and tools of the "overshot type may have solid discs 23-13 as shown in Fig. 12.

In Fig. 8 is shown a disc or gripping element 'l-B which may be used in lieu of the discs I should it be desirable to engage a hollow element having a hexagonal bore, and in Fig. 9 is shown a gripping element '|-C which may be similarly used in engaging a hollow element with a square bore.

Similarly, in Fig. 11 is illustrated a gripping element or disc 23-0 having a square orifice ll which may be embodied in an overshot for engaging a square "fish" such as a drill kelley. It will be noted that at each corner of the orifice ll, the disc is relieved by notches 42 so that the disc may bend slightly when engaging the fish. This principle is also carried out in the corners of the disc 'l-C (Fig. 9) by the provision of notches 43.

In Fig. 14 is shown a manner. in accordance with the invention, of attaching two elements 50 same general principle of frictional grip by one or more resilient deformable sheet gripping elements. Of course, the amount of required resiliency and distortion will vary according to the particular Job to be accomplished. It may also be seen that s we the gripping elements may be and 5! together upon a rod, bolt or similarmem-" ment, the usual spacers 24, as shown in Fig. 2, r

are supplanted by annular sealing elements 24-a of resilient material such as rubber or the like.

In using this embodiment, the "fish 2 entering the body 20 causes the inner edges of the elements 24-a to be sprung upwardly as shown.

The sealing elements 24a are of a suiiicient width between their outer and inner edges to span the distance between the fish and -the body 20, and consequently, any fluid pressure exerted downwardly within the body 20 will be forced by the sealing elements to flow through 'InFig. 16 is shown an embodiment of the invention in the form of a. spear, which is equipped with a sealing means similar in oillce to'that of Fig. 15. In this embodiment, which is similar in form to that of Fig. l, the spacers 8 have been supplanted by resilient annular spac- The operation of this embodiment is similar to that of Fig. 15 except that the elements 8-a seal with the inner wall of the From the foregoing description, it may be readily seen that although a number of mechanisms-have been disclosed, they all utilize the formed by a single die stamping operation, economy in manufacture is attained, and in each embodiment, the gripping elements may readily be replaced if broken.

I claim:

l. A gripping mechanism comprising a plurality of aligned resilient metal washers, the interior edge of each washer being provided with radial teeth which are distorted at an. angle from the plane of the body of the washer whereby the device may be unscrewed from a gripped object by rotation, annular spacers for the washers, a housing for the washers and spacers, and adjustable means for compressing the washers and spacers together within the housing.

2. A gripping mechanism for the interior of tubular elements, comprising a plurality of aligned resilient metal washers, the outer edge of each washer being provided with radial teeth which are distorted at an angle from the plane of the body of the washer whereby the device may be unscrewed from a gripped object by rotation, annular spacers for the washers, a rod passing through the washers and spacers, and means for rigidly clamping the inner edge portions of the elements and spacers together,

3. Organization as described in claim 1, in which the spacers are formed of a compressible material and are adapted to pack off between the rod and the tubular element.

4. A fishing tool comprising the combination with a body including rings of elastic non-metallic material, and metallic members constituting part of said body and exposed through the wall surfaces thereof, said members being spaced iongitudinally of said body by said rings, and teeth carried by the exposed portions of the members, said teeth being disposed at an obtuse angle with relation to .the axis of the body whereby the body may be unscrewed from an engaged object passing therethrough, and means for holding the rings and the metallic members in superimposed relation.

5. A fishing with a body material, and annular metallic members constituting part of said body and exposed through the inner wall/surfaces thereof, said members being spaced longitudinally of said body by said'rings, and teeth carried by the exposed portions of the members, said teeth being disposed at an obtuse angle with relation to the axis of the body whereby the body may be unscrewed from an engaged object passing therethrough, and means for holding the rings and the metallic members in superimposed relation.

6. A fishing tool comprising the combination with a body including rings of elastic nonmetallic material, and metallic members exposed through the surface of said body between said rings, teeth carried by the exposed portions of said members, said teeth disposed at an obtuse angle with relatool comprising the "combination 'tion to the axis of the body whereby the body may be unscrewed from an engaged object, and means for holding the rings and the metallic members in superimposed relation.

7.-A fishing tool comprising the combination with a body including rings of elastic nonmetallic material. and metallic members exposed through eluding rings of elastic nonmetallic- 4 assgsso body may be unscrewed roman engaged object 5 surrounding the body, and means for holding the rings and the metallic members in superimposed relation.

8. A fishing tool comprising the combination with a body including rings, and metallic memm bers constituting part of said body and exposed through the wall surfaces thereof. said members being spaced longitudinally of said body by said rings,andteethcarrledbytheexposedportionsot the members.saidteethbeingdisposedatan obtuse angle with relationto the axis otthe body whereby the body may be, unscrewed from an engaged object, and means (or holding the rings and themetallic members in superimposed relatlon.

IRAN; M. OWEN. 

